Hierarchical electrospun shape memory composite fibers as self-sensory actuators

Abstract

Electrospun shape memory polymer mats, depositing with carbon nanotubes (CNTs) at the aid of polydopamine (PDA), were twisted into fibers in unique hierarchically coiled structures consisting of locally aligned micro/nano fibril bundles. Twisting with certain turns greatly strengthened the mechanical properties meanwhile reduced hysteresis in stretching/releasing cycles. The reversibility and stability of resistive-type strain sensing of the twisted fibers were improved. Combined with shape memory actuation, photothermal effect and strain sensing, the twisted fibers were explored light-triggered self-sensing actuators. The findings may benefit exploration of electrospun intelligent polymers as artificial muscles and soft actuators.